The role of person familiarity in young infants' perception of emotional expressions

This research investigated the role of person familiarity in the ability of 3.5-month-old infants to recognize emotional expressions. Infants (N = 72) were presented simultaneously with two filmed facial expressions, happy an d sad, accompanied by a single vocal expression that was concordant with on e of the two facial expressions. Wants' looking preferences and facial expr essions were coded. Results indicated that when the emotional expressions w ere portrayed by each infant's own mother, infants looked significantly lon ger toward the facial expressions that were accompanied by affectively matc hing vocal expressions. Infants who were presented with emotional expressio ns of an unfamiliar woman did not. Even when a brief delay was inserted bet ween the presentation of facial and vocal expressions, infants who were pre sented with emotional expressions of their own mothers looked longer at the facial expression that was sound specified, indicating that some factor ot her than temporal synchrony guided their looking preferences. When infants viewed the films of their own mothers, they were more interactive and expre ssed more positive and less negative affect. Moreover, infants produced a g reater number of full and bright smiles when the sound-specified emotion wa s "happy," and particularly when they viewed the happy expressions of their own mothers. The average duration of negative affect was significantly lon ger for infants who observed the unfamiliar woman than for those who observ ed their own mothers. These results show that when more contextual informat ion-that is, person familiarity-was available, infants as young as 3.5 mont hs of age recognized happy and sad expressions. These findings suggest that in the early stages of development, infants are sensitive to contextual in formation that potentially facilitates some of the meaning of others' emoti onal expressions.